Search Publications
Revealing the Star-Disk-Jet Connection in GM Aur Using Multiwavelength Variability
Hernández, J.; Macías, E.; Espaillat, C. C. +1 more
We analyze the first simultaneous X-ray, ultraviolet, optical, infrared, and centimeter observations of a T Tauri star (TTS). We present three epochs of simultaneous Spitzer and Very Large Array data of GM Aur separated by ∼1 week. These data are compared to previously published Hubble Space Telescope and Chandra observations from which mass accre…
Jellyfish: Resolving the Kinematics of Extreme Ram-pressure Stripping at z ∼ 0.3
Ebeling, Harald; Kalita, Boris S.
We present and discuss results from the first spatially resolved kinematic study of ram-pressure stripping of a massive late-type galaxy at intermediate redshifts. Our target, the spectacular “jellyfish” galaxy, A1758N_JFG1, was previously identified as a fast-moving member of the equal-mass merger A1758N (z = 0.28), with a star formation rate of …
Towards New Comet Missions
Kührt, E.; Gundlach, B.; Thomas, N. +6 more
The Rosetta observations have greatly advanced our knowledge of the cometary nucleus and its immediate environment. However, constraints on the mission (both planned and unplanned), the only partially successful Philae lander, and other instrumental issues have inevitably resulted in open questions. Surprising results from the many successful Rose…
Heavy metal enrichment in the intermediate He-sdOB pulsator Feige 46
Heber, U.; Latour, M.; Dorsch, M.
The intermediate He-enriched hot subdwarf star Feige 46 was recently reported as the second member of the V366 Aqr (or He-sdOBV) pulsating class. Feige 46 is very similar to the prototype of the class, LS IV - 14°116, not only in terms of pulsational properties, but also in terms of atmospheric parameters and kinematic properties. LS IV - 14°116 i…
Spectral observations of X Persei: Connection between Hα and X-ray emission
Zamanov, R.; Stoyanov, K. A.; Wolter, U. +2 more
We present spectroscopic observations of the Be/X-ray binary X Per obtained during the period 1999-2018. Using new and published data, we found that during "disc-rise" the expansion velocity of the circumstellar disc is 0.4-0.7 km s-1. Our results suggest that the disc radius in recent decades show evidence of resonant truncation of the…
The Massive and Distant Clusters of WISE Survey. VI. Stellar Mass Fractions of a Sample of High-redshift Infrared-selected Clusters
Gupta, Nikhel; Eisenhardt, Peter R. M.; Gonzalez, Anthony H. +17 more
We present measurements of the stellar mass fractions ({f}\star ) for a sample of high-redshift (0.93 ≤ z ≤ 1.32) infrared-selected galaxy clusters from the Massive and Distant Clusters of WISE Survey (MaDCoWS) and compare them to the stellar mass fractions of Sunyaev-Zel’dovich (SZ) effect-selected clusters in a similar mass and redshi…
On the photometric signature of fast rotators
Girardi, Léo; Marigo, Paola; Bellini, Andrea +4 more
Rapidly rotating stars have been recently recognized as having a major role in the interpretation of colour-magnitude diagrams of young and intermediate-age star clusters in the Magellanic Clouds and in the Milky Way. In this work, we evaluate the distinctive spectra and distributions in colour-colour space that follow from the presence of a subst…
Spectroscopic Orbits of Subsystems in Multiple Stars. V.
Tokovinin, Andrei
Spectroscopic orbits are determined for inner subsystems in nine stellar hierarchies (HIP 2863, 4974, 8353, 28796, 35261, 92929, 115272, 115552, and 117596). Their periods range from 2.5 to 312 days. For each system, estimates of masses, orbital inclination, and other parameters are given.
Transition-region explosive events produced by plasmoid instability
Li, Dong
Magnetic reconnection is thought to be a key process in most solar eruptions. Thanks to highresolution observations and simulations, the studied scale of the reconnection process has become smaller and smaller. Spectroscopic observations show that the reconnection site can be very small, which always exhibits a bright core and two extended wings w…
Recognition of M-type stars in the unclassified spectra of LAMOST DR5 using a hash-learning method
Luo, A. -L.; Chen, J. -J.; Du, B. +6 more
Our study aims to recognize M-type stars which are classified as `UNKNOWN' due to poor quality in the Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) DR5 V1. A binary nonlinear hashing algorithm based on Multi-Layer Pseudo-Inverse Learning (ML-PIL) is proposed to effectively learn spectral features for M-type-star detection, whi…